The Indiana State Department of Health (ISDH) recently withdrew its proposed
residential onsite wastewater rule because it became apparent that there was no
pretreatment system available (sand filters, wetlands, etc) that could
consistently treat septic tank effluent to meet drinking water standards for
nitrates. Why would we need a septic system that could do that? It turns out
that the federal government several years ago developed “ground water
protection” standards, with the intent that no material reaching the ground
water with more than 10 ppm (parts per million) of nitrate nitrogen, which is
also the maximum allowed in drinking water. The primary issue here is where the
"groundwater" impact is measured. The ISDH is working with other government
agencies to find a resolution to the situation. Just where this will leave
septics is not yet clear. The other industry that could be affected is
Agriculture. Indiana does a lot of things well, but none better than raising
crops and livestock. This would not be possible without commercial fertilizer
(including nitrogen). Given what is at stake, this regulation may yet exempt
various activities, or at least be muted in its impact on those activities. The
future of onsite systems in Indiana is to be decided soon in Indianapolis.
Potentially, some soils may need recirculating sand filters or other treatments
to reduce nitrogen levels going to the absorption field. Hopefully this will all
be revealed by the time our next (and last) newsletter reaches you in about
three months. How
can nitrogen be removed from septic tank effluent?

The possibility of groundwater contamination from on-site sewage disposal
systems by nitrates appears to increase when homes with onsite disposal systems
are closely spaced, have a well aerated unsaturated soil zone, or are on soils
with low C.E.C. or low moisture holding capacity.

The previous article explains that lower nitrogen levels may be needed in the
effluent entering the absorption areas in some soils. Fortunately, there are
several pretreatment systems that can do this. Virtually all use a natural
biological process called nitrification-denitrification. Basically,
nitrification is the conversion of nitrogen into nitrate and denitrification is
the conversion of nitrate into nitrogen gas. This is the most
environmentally-friendly way to remove nitrogen, since nitrogen is released as
nitrogen gas (N2) which is naturally occurring (nitrogen gas makes up
nearly 80% of the air we breathe).

(The drinking water limit (10 ppm) is listed as nitrate-nitrogen, or nitrate
as nitrogen (NO3-N). This is not the same as 10 ppm of nitrate. The
difference is in the molecular weight. Nitrogen has a molecular weight of 14,
nearly the same as oxygen (16), which makes up most of the rest of air.
Nitrate-nitrogen reflects the amount of N, which if measured in nitrate
(NO3) would be about 4 1/2 times higher (10 ppm NO3-N =45
ppm Nitrate). Most nitrogen concentrations, whether nitrate or ammonium, are
expressed as nitrogen (NO3 –N or NH3-N) to put things on a
common footing.)

Okay, back to nitrification-denitrification. The nitrogen found in septic
effluent is approximately 25% organic and 75% soluble ammonium nitrogen
(NH4-N). Septic tank effluent typically averages 40 to 80 parts per
million (ppm) nitrogen per household a year. When nitrogen in wastewater is
aerated, it becomes nitrate (NO3). Nitrate is very mobile insoil and any that is not taken up quickly by the plant roots can
end up in a tile line or the ground water. Since onsite systems normally
discharge effluent below the root zones (usually not more than 2 ½ inches deep
for grass), this is a concern. By recycling the aerated or nitrified
(NO3) effluent back to the anaerobic (no air present) material in the
recirculation tank, bacteria in the waste quickly use the oxygen attached to the
nitrogen in NO3 (denitrifcation), This releases the nitrogen gas
(Figure 1).

Recirculating sand filters work very hard at this
nitrification-denitrification process, recycling between the aerobic environment
of the sand filter and the anaerobic one of the recirculation tank as many as
four or five times.

It is also possible to accomplish this with an aerobic treatment system where
the effluent is recycled back to the chamber containing tank effluent ahead of
the aeration unit. Another method is to operate the aerator on a timer so that
is continuously switches between aerobic-anaerobic environments.

Wetlands today are very effective at organic treatment, but are not designed
for nitrogen removal. It might be necessary to precede the wetland with an
aeration system, or oversize the wetland to ensure an aerobic environment and
recycle the effluent back through the wetland several times.

Figure 1. Recirculating Sand Filter

Landscaping Septic
Systems

If you have a mound system, or are planning to install one, and are looking
at landscaping options; the University of Minnesota Extension Service has a
4-page brochure that can help. The best suggestion for "camouflaging" your mound
system is to start during the planning stages and fit the landscaping to the
acceptable areas of your lot. This booklet includes a couple of design ideas, as
well as a list of plants that are hardy in dry conditions. Water-loving plants
should never be used near an absorption field and trees that seek water
reservoirs (poplar, maple, willow, elm) must be planted at least 50 feet away.
This publication can be ordered directly from UM Extension at 1-800-876-8636 for
$0.75 each (call for bulk discounts). [Alert: Due to a
typesetting error in the University of Minnesota Extension Service publication,
the toll-free number was listed as "1-800-976-8636" in the hard-copy format of
this newsletter. We truly regret any inconvenience and embarrassment caused by
this error.]

Construction Open
House at Purdue Throckmorton Farm

Reducing the environmental impacts of septics in many cases will require more
complex and more expensive pretreatment of septic effluent before it is
discharged to the soil. In order to encourage interest in pretreatment systems,
a 4-day construction open house was held at Purdue's Throckmorton farm beginning
on May 30, 2000, 10 miles south of Lafayette on US 231, where a recirculation
sand filter, drip irrigation system, and graveless shallow trench system were
installed to treat the 2100 gallons of domestic wastewater that will be
generated each day. Ninety contractors and county health officers attended at
least a portion of this open house. Hack Excavating did the installation and
Earthtek did the design using components from Zabele , Orencoe ,
PM Associatese and Hartford City Concrete.
Goff Electric wired the pumps and installed the electrical controls. A number of
staff from the ISDH attended and Ron Noles, Tippecanoe County Health Office, was
there nearly every day. Thanks very much to all these folks for their excellent
help.

The Throckmorton farm will become the headquarters for Purdue's Horticulture
field work and is expected to be a very popular place, particularly in the
summer and fall with many people stopping to buy produce. A large display
showing the layout plans will be located beside the control panel for the pumps.

Wastewater Treatment
Programs Serving Small Communities

A surprising number of households in Indiana still lack adequate sewage
facilities. The US EPA has published a brochure that aims to help these
households and their communities get information that can help solve the
problem.

It provides an overview of nine EPA-funded programs that offer training,
financial and technical assistance, and outreach to small communities to help
improve their wastewater facilities. There is also a contact information/hotline
list including a contact for each particular program. It is available from the
EPA's Office of Water Resources Center (202/260-7786 - refer to document number
EPA-832-R-00-002) and online at www.epa.gov/OW/smallc.htm under the "small
communities publications" button.

Homer & Maud Homeowner

Homer & Maud Homeowner

"Percolation Rate" -- Homer and Maud Style!

Terminology For
Onsite Systems

manhole: see inspection port

mastic: putty-like materials that are used to coat or cement various
parts of a septic system to seal it or make it watertight

microorganism: any living creature, including bacteria, viruses, and
protozoan, of microscopic or submicroscopic size

mound: a type of soil absorption area that is raised above the natural
soil surface using an appropriate fill material; smaller than a raised-bed
system; used when the depth of permeable soil is less than the required 4 feet
or in areas of high water table

National Sanitation Foundation (NSF): a non-profit organization that
certifies the construction of components and materials in wastewater treatment
systems

onsite sewage treatment: a general term referring to any of the
various systems for treating waste emanating from a household plumbing fixture
or water treatment unit

organic mat: the microorganisms and organic matter that build up
around a soil absorption areaat the media-soil interface;
can be especially prevalent with sandfilters

organic matter: any material derived from living things

outhouse: a small, shed-like structure, away from the main dwelling
that houses a waterless toilet. Synonym: privy

percolation or perc test: an old method of determining the suitability
of the soil for an absorption area; a test hole is dug, water added to the hole,
and the rate of infiltration of water into the soil is determined

percolation rate: see infiltration rate

perforated pipe/tile: the pipe in an absorption area that contains
regularly-spaced holes to release effluent into the media such as sand or
aggregate and then into the soil

permeable: allowing liquid to pass through; used when describing soil
absorption systems and their suitability for sewage treatment. Antonym:
impermeable

pressure distribution: using a pump to distribute septic tank or
aerobic unit effluent through the pipe network of a soil absorption area
resulting in a more even distribution of effluent over the soil than does
gravity distribution

primary treatment: the treatment of household sewage that takes place
in a septic tank, separates floating and settleable soils from raw wastewater

raised system: an absorption trench system constructed in appropriate
fill material placed above the natural soil surface; larger than a mound system

IOWPA hopes to work closely with manufacturers for new product information
and training, improving communication between allmembers
of our association, and better understanding of the issues that affect Indiana
citizens who live beyond the reach of sanitary sewers.

The mission statement of IOWPA is: To educate and to promote a high standard
of workmanship by encouraging a code of ethics among our members who are
committed to protecting the waters of Indiana.

To provide the onsite wastewater industry in Indiana with a strong and
unified voice that represents the common interests and concerns of its members
on a statewide level.

Prompted by the implementation of the Environmental Management Code 320IAC8
in October of 1984, Indiana septic tank cleaners and their affiliates formed the
Northern Indiana Pumpers Association (NIPA). NIPA initiated a statewide effort
to alter some of the rules that thei members felt were too difficult to comply
with. Due to the overwhelming response of septic tank cleaners across the state,
the Indiana Pumpers Association was formed.

In January 1997 the name was changed to the Indiana Septic Association (ISA)
with the intention of clarifying its purpose. An Executive Director was
appointed and our quarterly newsletter "ON PRO" was published.

Later that year, by popular vote at their annual conference, the name was
finally changed to the Indiana Onsite Wastewater Professionals Association
(IOWPA).

The purpose for these changes was to encourage participation by all
professionals active in the onsite wastewater industry. The Association now
includes cleaners, system installers, wastewater plant operators, product
manufacturers, educators, engineers, and regulators. Annual registration fee is
$50 for individual or $100 for corporate members. Our Board of Directors
consists of representatives from all these professions.

Following is a list of our current Officers. Feel free to contact any of them
if you should have questions or would like to learn more about IOWPA.

On April 4, Alan Dunn, manager of the Residential Sewage Disposal Dept. in
the Sanitary Engineering Division, received the State Health Commissioner Award
for his technical expertise and assistance on soils, septic system design, rule
interpretation, and expert dispute resolution among the disparate interests of
engineers, contractors, manufacturers, and suppliers. Congratulations, Alan!

ONSITE ONLINE

Groundwater Database, Inc.

This web site offers several options including Septic System
Tracking and can be customized to a particular customer's requirements. Check it
out: http://www.waterweb-gwdb.com

This publication from Ohio State University Extension is
directed at designers and regulators of wastewater treatment systems. It
includes information on single pass and recirculating sand bioreactors (or
filters), as well as different styles and designs (open, buried, and covered).
There is also detailed information on construction, media requirements, dosing
options, and pretreatment, and disinfection (particularly UV disinfection).
Other sections address the advantages and disadvantages, details on operation
and maintenance, and troubleshooting. The section on regulations and permits
applies specifically to Ohio regulations. This publication is available for loan
from our office (carols@purdue.edu or
765/494-1174) or directly from The Ohio State University Extension online at http://ohioline.ag.ohio-state.edu/b876/b876_11.html

The price is $1.50 per copy with a 20% discount for orders of
50 copies or more.

RWASTE

http://danpatch.ecn.purdue.edu/~onsite/
is the home of Purdue's online septic system design program. It now designs
conventional onsite soil absorption systems as well as elevated sand mounds.
This program is based on the proposed ISDH rule and on MWPS-24, "Onsite Domestic
Sewage Disposal." The user must provide information on their proposed site as
slope, depth to groundwater, and a soil profile.

Mandated Certification of Onsite
Professionals

According to the article in Small Flows Quarterly, the following table
represents the current status of onsite certification by state:

State

Contractors

Installers

Inspectors

Pumpers

Designers

Engineers

Geologists

Operators

AL

Y

Y

Y

Y

N

Y

Y

Y

AK

Y

Y

NA

NA

NA

Y

NA

NA

AZ

Y

Y

NA

Y

NA

Y

Y

NA

AR

N

Y

N

Y

Y

N

N

N

CA

N

N

N

N

N

N

N

N

CO

N

N

N

N

N

Y

N

Y

CT

NA

Y

Y

Y

NA

Y

NA

NA

DE

Y

Y

N

Y

Y

Y

N

Y

FL

Y

Y

Y

Y

Y

Y

Y

Y

GA

Y

Y

Y

Y

N

N

N

N

HI

N

N

N

N

N

Y

N

Y

ID

N

Y

Y

Y

N

N

N

N

IL

Y

Y

NA

Y

NA

NA

NA

NA

IN

N

N

N

N

N

N

N

N

IA

N

N

N

Y

N

N

N

N

KS

NA

NA

NA

NA

NA

Y

Y

Y

KY

Y

Y

Y

Y

N

N

N

N

LA

NA

Y

NA

NA

NA

NA

NA

NA

ME

N

Y

Y

N

Y

Y

Y

N

MD

N

Y

Y

N

N

N

N

N

MA

Y

Y

Y

Y

Y

Y

N

Y

MI

N

N

N

N

N

N

N

N

MN

NA

Y

Y

Y

Y

NA

NA

Y

MS

NA

Y

Y

Y

NA

NA

NA

NA

MO

Y

N

N

Y

N

Y

N

N

MT

N

N

N

N

N

N

N

N

NE

N

N

N

N

N

N

N

N

NV

NA

NA

NA

NA

NA

NA

NA

NA

NH

N

Y

N

N

Y

Y

N

Y

NJ

N

N

N

N

N

N

N

N

NM

Y

Y

N

N

N

N

N

N

NY

N

N

N

Y

N

N

N

N

NC

N

N

Y

N

N

N

N

N

ND

Y

Y

Y

N

N

N

N

N

OH

N

N

N

N

N

N

N

N

OK

Y

Y

N

Y

Y

N

N

Y

OR

Y

Y

Y

Y

Y

Y

Y

Y

PA

N

N

Y

N

N

Y

Y

N

RI

Y

Y

Y

N

Y

Y

N

Y

SC

Y

Y

NA

Y

NA

NA

NA

NA

SD

N

Y

N

N

N

N

N

N

TN

N

Y

N

Y

N

Y

Y

Y

TY

N

Y

Y

Y

N

N

N

Y

UT

N

N

N

N

N

N

N

N

VT

N

N

N

N

Y

N

N

Y

WA

N

N

N

N

N

Y

Y

Y

WV

N

Y

N

Y

N

N

N

N

WI

N

Y

Y

Y

Y

Y

Y

N

WY

N

N

N

N

Y

Y

Y

N

NA = not available

Marilyn Noah, taken from Small Flows Quarterly, National
Small Flows Clearinghouse, Winter 2000, Volume 1, Number 1.